<div class="header">
  <button (click)="toggleVisibility()">
    [{{hidden ? showCommentText : '-'}}]
  </button>
  <span>{{comment['user']}} {{comment['time_ago']}}</span>
</div>
<div [hidden]="hidden">
  <div class="content" [innerHtml]="content"></div>
  <comment
      *ngForIdentity="let comment of comment['comments']"
      [comment]="comment">
  </comment>
</div>
